The X-Aptamer Selection Kit (XASK) makes aptamers much more accessible to the life science market. The low-priced kit greatly minimizes the expertise and equipment required to perform aptamer selections; thus, enabling virtually any scientist with basic laboratory skills to rapidly develop his or her own synthetic next generation X-Aptamer (XA) affinity reagents. The Phase I SBIR successfully answered several fundamental questions associated with the bead-based selection technology underlying the XASK. It also conclusively demonstrated the feasibility of the kit as a commercial product. Several independent users successfully selected X-Aptamers using XASK prototypes, which far exceeded the anticipated outcome from Phase I. X-Aptamers are chemically-modified DNA affinity agents that utilize amino acid functional groups and even small molecules to enhance interaction with targets. XAs routinely exhibit nanomolar to picomolar binding affinity as well as excellent specificity, making them a promising synthetic alternative to antibodies. AM Biotech has developed a rapid, single-cycle XA discovery process that is not based on SELEX. The process is performed in two easy steps using bead-based oligonucleotide libraries and standard laboratory equipment that enable packaging the discovery processes into XASK. The Phase II SBIR will focus on; 1) enhancing the quality of the critically important bead-based libraries, and 2) optimizing the bead-based selection process to improve the success rate to >85%. The XASK is a revolutionary product that will disrupt the aptamer market and will begin to make inroads into the antibody market. AM Biotech believes that the XASK and X-Aptamers are poised for strong market penetration that will help to pull aptamers into many commercial applications.